Locking device for retractable handle of luggage

ABSTRACT

A handle assembly of luggage comprised of a handle grip with a push button, two first sliding tubes, at least one pair of second sliding tubes, two supporting tubes, two first locking devices, each provided below each first sliding tube, at least one pair of second locking devices, each provided below each second sliding tube, a pair of first connecting means attached between the handle grip and the first locking devices, and at least one pair of the second connecting means for controlling the second locking devices. The length of the fully extended handle is expected to be longer than the height of the luggage body so as to provide the user with a luggage handle which can be extended to a sufficient height to meet the user&#39;s various towing needs.

CROSS-REFERENCE TO RELATED APPLICATION

[0001] Reference is made to pending application (Attorney Docket No.890.003.018), entitled LOCKING DEVICE WITH IMPROVED JUMPING MEANS FORRETRACTABLE HANDLE OF LUGGAGE, assigned to the assignee of thisapplication and filed on even date herewith.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to a retractable handle of luggageand more particularly to a locking device for a retractable handle ofluggage.

[0004] 2. Description of Related Art

[0005] Conventionally, a retractable luggage handle uses a single-strokelocking device and is equipped with only one locking device to controlthe luggage handle's movement. This one locking device is usuallyinstalled at the bottom of a single sliding tube and is provided as amedium element between the one sliding tube and a supporting tube.However, it is possible to design the locking device's sliding tube insuch a manner that the engagement between the sliding tube and thesupporting tube is done through a plurality of retaining slots providedon the supporting tube. As a result, more height options are created forthe retractable handle. Conventionally, the length of an extendableluggage handle, which precedes the full height of an upright luggageshould be no taller than the height of the luggage case itself. WarsawConvention also stipulates the permissible maximum dimensions forcarry-on luggage. Therefore, the total bulk height of an upright luggagebody, plus the extra height spanned by a fully extended luggage handle,should still be shorter than the straight-line distance measured fromthe draping fingertips of a naturally-posed, standing individual to theground. This means that the user is often urged to bend his/her back toreach the luggage handle in order to get hold of the luggage. It isobvious that the conventional design is not a handy design for mostusers.

[0006] Moreover, in order for the user to move his/her luggage in andout of luggage storage areas inside an airplane or an automobile, theuser often needs to retract the handle to its lowest position to performa smooth loading task. Since, in the conventional design, there is onlyone retraction stroke provided on the locking device of the luggagehandle, the lowest position of the handle grip also means the closure ofthe sliding tube to the supporting tube of the luggage handle. That isto say, no allowance is ever given between the user's handhold positionand the luggage body when the user is trying to partially retract thehandle and move it to the luggage storage space in a transportationvehicle. Such a luggage handle's on-the-run positioning leads to anunfavorable physical placement of the luggage body, which in turn causesthe center line of the luggage handle grip to be tilted away from thecenter line of the luggage body when the luggage is lifted. In otherwords, the lower portion of the luggage will come nearer to the userthan the top portion thereof. Thus, the unfavorable physical position ofa dangling piece of luggage interferes with the user's physicalmovement.

SUMMARY OF THE INVENTION

[0007] It is therefore an objective of the present invention to producea multi-stroke locking device for the retractable handle of a luggagepiece in order to minimize the problems which were encountered in theprior art.

[0008] Another objective of the present invention is to produce alocking device for the retractable handle of a luggage piece, whereinthe mechanical structure of the new locking device is generallysimplified so as to effect a quick assembly in the manufacturingprocess.

[0009] It is still another objective of the present invention to producea locking device for the retractable handle of a luggage piece, whereinthe handle grip can be raised a small distance in height from its bezelrecess located on top of the luggage and also be locked there so as tobe used as a carry-on handle for the luggage for the possibility oftilting when it is lifted. Consequently, such a new design will improvethe luggage's balance when the user is attempting to use as a carry-onhandle.

[0010] To achieve the above mentioned and other objectives, the presentinvention embodies a handle system for the luggage which comprises twosymmetrically identical portions, each having a handle grip and a pushbutton thereon, a first sliding tube affixed to the end of the handlegrip, a first locking device detachably attached to the bottom of thefirst sliding tube, a second sliding tube with a plurality of holesdrilled upon it for allowing the first sliding tube to glide freelytherein, a second locking device detachably attached to the bottom ofthe second sliding tube, a supporting tube with a plurality of holesdrilled upon it for allowing the second sliding tube to glide freelytherein, and a first connecting means linked between the push button andthe first locking device; wherein the second locking device comprises anupper portion, a lower portion, a sliding block longitudinally slidablewithin the upper portion, a spring laterally biased in the lowerportion, a locking block laterally slidable within the lower portion,and a second connecting means having the top end clung to the firstlocking device and the bottom end clung to the longitudinally allocatedsliding block.

[0011] The above and other objectives, features, and advantages of thepresent invention will become apparent from the following detaileddescription made in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012]FIG. 1 is an exploded view of a preferred embodiment of a lockingdevice for the retractable handle of luggage according to the invention;

[0013]FIGS. 2A and 2B are first and second sectional views showing theretracted positions of the fully retracted handle, respectively;

[0014]FIGS. 3A and 3B are similar to FIGS. 2A and 2B, respectively,where the push button is pressed to cause the handle grip to be pulledup a small distance from the bezel recess located on top of the luggageand be fixedly locked thereat;

[0015]FIGS. 4A and 4B are similar to FIGS. 3A and 3B, respectively,where the push button is again pressed to cause the handle grip to bepulled up again so that the first locking device is locked into theupper hole of the second sliding tube and the second locking device islocked into the lower hole of the supporting tube;

[0016]FIGS. 5A and 5B are similar to FIGS. 4A and 4B, respectively,where the push button is pressed again to cause the handle grip to befurther pulled up so that the first locking device is cleared from theupper hole of the second sliding tube, and the second locking device ismoved up;

[0017]FIGS. 6A and 6B are similar to FIGS. 5A and 5B, respectively,where the second locking device is locked into the upper hole of thesupporting tube so as to pull the second locking device in an extensionposition, and the first locking device is pull by the steel cable andretracted into the second sliding tube;

[0018]FIGS. 7A and 7B are similar to FIGS. 6A and 6B respectively, wherethe handle is fully extended and locked; and

[0019]FIGS. 8A and 8B are similar to FIGS. 7A and 7B, respectively,where the first locking device is retracted into the second sliding tubeby pressing the push button so that the bottom of the first lockingdevice is engaged with the top of the second locking device, wherein thelock pin of the second locking device is not fully extended such thatthe second locking device is suppressed by the first locking device toclear the second locking device from the upper hole of the supportingtube.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020]FIG. 1 shows a multi-stroke locking device for the retractablehandle of a luggage piece constructed in accordance with the presentinvention, wherein the handle system is provided at the back of theluggage with a handle grip retractable to a recess located on top of theluggage.

[0021] Note that since the present handle assembly is bilaterallysymmetric, the description on one side of the handle system serves tospeak for both the entities. The handle system of the present inventioncomprises a first sliding tube 10, a first locking device 20, a firstsleeve member 30, a second sliding tube 40, a second locking device 50,a second sleeve member 60, and a supporting tube 70. The first slidingtube 10 has a lower hole 13 and an upper hole 12; the upper hole 12 isconnected to the receiving opening on one side of the handle grip (notshown) by a known fastener. The first locking device 20 is detachablyattached to the bottom of the first sliding tube 10. The second slidingtube 40 is provided to allow the first sliding tube 10 to glide freelytherein and contains the top, middle, and lower holes 45, 46, and 47 ona first side, two apertures 42 on the first and third sides, and two pinholes 43 on a second and fourth side. The first sleeve member 30 isfitted to the top of the second sliding tube 40 and has two slightlyprotruded projections 32 located at the two opposite sides of the sleevemember's 30 outer surface; the two projections 32 are provided to couplewith the two apertures 42 of the second sliding tube 40. The secondlocking device 50 is detachably attached to the bottom of the secondsliding tube 40 and is secured to the second sliding tube 40 by a pin44. The supporting tube 70 is provided to allow the second sliding tube40 to glide freely therein; the supporting tube 70 contains the top andlower holes 73 and 74 on a first side, two apertures 72 on the first andthird sides, and two pin holes 75 symmetrically sited on the first andthird sides, while one is below the lower hole 74. The second sleevemember 60 is installed on the top of the supporting tube 70 and has twoslightly protruded projections 62 located at the two opposite sides ofthe sleeve member's 60 outer surface; the two projections 62 areprovided to couple with the two apertures 72 on the upper part of thesupporting tube 70.

[0022] The first locking device 20 comprises a first housing 21, a firstconnecting means 22, a helical spring 23, and a first locking block 24.The first housing 21 contains an upper portion 210 and a lower portion214. The upper portion 210 consists of a longitudinal guide groove 212,a longitudinal retaining groove 211, and a laterally traversed pin hole213 such that the pin 14 may be inserted through the lower holes 13 ofthe first sliding tube 10 and the pin hole 213 to secure the firstlocking device 20 to the first sliding tube 10. The lower portion 214contains a lateral tunnel cavity 215 and a smoothly curved portion 218(see FIGS. 2A-7A). The helical spring 23 is laterally provided insidethe tunnel opening 215 at the bottom of the first housing 21 to bebiased against the first locking block 24 for completing the operationof locking or unlocking it. The first locking block 24 is provided to beinserted into the lateral cavity 215 within the lower part of the firsthousing 21 and contains a projection 240 on a first side, an aperture241 on a second side, and an opening 245 which is in communication withthe side aperture 241. The first connecting means 22, in the form of acurvilinearly deformable steel cable, has two enlargements provided atthe two ends. One end of the enlargements (not shown) is secured to thehandle grip 90, and the other end 221 is secured into the hollow opening245 on the first locking block 24 through a path, which starts from thelongitudinal retaining groove 211, the smoothly curved portion 218, thelateral cavity 215, and reaches the hollow opening 245 of the firstlocking block 24 such that the mere pressing of the push button 91 onthe handle grip 90 may actuate the first locking device 20 through themovement of the steel cable 22.

[0023] The second locking device 50 is formed by a second lockinghousing 50A, which has an upper portion 51 and a lower portion 52. Theupper portion 51 contains a longitudinal groove 511 and two laterallytraversed pin holes 512 (these two pin holes serve as the two openingmouths of the laterally penetrated pin tunnel) such that the pin 44 maybe inserted through the lower hole 43 of the second sliding tube 40 andthe pin holes 512 to secure the second locking device 50 and the secondsliding tube 40 together. The lower portion 52 consists of a laterallyallocated central dent 521, a circular indentation 523 opened at thewalled end of the central dent 521, a helical spring 53, a generallycubic shaped locking block 54, a longitudinal sliding block 55, and asecond connecting means 56. The helical spring 53 is horizontally placedinto the laterally disposed central dent 521 at the lower portion 52 ofthe second housing 50A and has one end biased against the circularindentation 523 on the walled end of the central dent 521. The generallycubic shaped locking block 54 goes against the helical spring's 53 otherend and is horizontally slidable within the central dent 521 at thelower portion 52 of the second locking housing 50A. With one end biasedagainst the helical spring 53, the locking block 54 contains a frontallock pin 541 and two triangular projections 542 symmetrically providedat the two opposing board sides of the locking block's 54 outer surface.The lock pin 541 is to go into the lower portion 553 of the longitudinalsliding block 55 to facilitate the coupling operation between the twotriangular projections 542 and the two V-shaped recesses 555 of thelower portion 553 of the sliding block 55; each of the two triangularprojections 542 has a lower slope 5421 and an upper slope 5422.

[0024] The sliding block 55 is longitudinally slidable along the groove511 of the upper portion 51 of the second locking housing 50A and duringsliding, the sliding block 55 glides itself through the mouth of thehorizontally disposed central dent 521 of the lower portion 52 of thesecond locking housing 50A. The sliding block 55 has an upper portion551 and a lower portion 553. The upper portion 551 has a protrudedgroove 552 on top and a longitudinal tracking surface below it. Thelower portion 553 has a side profile wider than the upper portion 551and contains a longitudinally deployed rectangular recess 557 and twoV-shaped recesses 555. The rectangular recess 557 is provided tocommunicate with the upper portion 551, and the two V-shaped recesses555 are located on the two opposite sides of the sliding block's 55outer surface; each of the two V-shaped recess 555 has an upper slope554 and a lower slope 556. The second connecting means 56, in the formof a slim rigid metal section, has a top hook end 561 clung to the guidegroove 212 of the first housing 21 of the first locking device 20 and abottom hook end 562 clung to the arch-shaped hook receiver 552 on theupper portion 551 of the sliding block 55.

[0025] The following narrative is a description of the operationprocedure for the handle system of the present invention. To provide aproper setting to accommodate the forthcoming discussion, the luggagehandle's locking device is initially assumed to be at its dormantretracted position. By making references to the adjoined illustrationsFIGS. 2A-8A, the following narrative can be best understood.

[0026] Originally, when the push button 91 is not pressed by the user,the handle 90 is at its recessed position (see FIGS. 2A and 2B). At thisstage, the first sliding tube 10 is retracted into the second slidingtube 40 and the second sliding tube 40 is retracted into the supportingtube 70. While the retraction of the first sliding tube 10 into thesecond sliding tube 40 is accomplished because the projection 240 of thelocking block 24 is biased by the spring 23 to engage with the lowerhole 47 of the second sliding tube 40, the retraction of the secondsliding tube 40 into the supporting tube 70 is achieved because thebottom of the first locking device 20 is biased against the top of thesliding block 55 of the second locking device 50 and thus incurs thefirst end 5411 of the lock pin 541 of the locking block 54 (see FIG. 2A)to engage with the lower hole 74 of the supporting tube 70. Thus, theluggage handle is locked at its retracted position. However, theengagement of the locking pin 541 to the lower hole 74 of the supportingtube 70, unlike the engagement of the guide pin 240 to the lower hole 47of the second sliding tube 40, does not mean the handle is fully locked.The reason for this is that, at the initial stage of the locking device,i.e., when neither the first nor the second sliding tube is protracted,the bottom of the first locking device 20 is biased against the top ofthe longitudinal sliding block 55 of the second locking device 50 andthus pushes it down to descend over the exact mating position whichleads to a full locking of the lock pin 541 provided on the lockingblock 54. Therefore, only the first end 5411 of the lock pin 541 of thelocking block 54 is induced to engage with the lower hole 74 of thesupporting tube 70.

[0027] When the push button 91 is first pressed down by the user, asshown in FIGS. 3A-3B, the cable 22 is instantly strained to move upwardto induce compression force to the spring 23, displace the locking block24, and withdraw the guide pin 240 from its initial position at thelower hole 47. This is the disengagement action of the projected guidepin 240 on the locking block 24 from the lower hole 47 of the secondsliding tube 40. The handle is then pulled up by the user to cause thelocking block 24, now disengaged from the hole 47, to begin to move fromits original position at the lower hole 47 to a second position at thecenter hole 46 on the second sliding tube 40 (see FIG. 3A). The firstlocking device 20 is therefore relocated to a new elevated position.Concurrently, the user's grasp of the handle grip 90 and raising of thefirst sliding tube 10 causes the lateral locking block 54 to be fullyengaged into the lower hole 74 of the supporting tube 70. When the userpulls up the first sliding tube 10, the bottom of the first lockingdevice 20 is separated from the top of the second locking device 50.Since, at this moment, the top of the sliding block 55 is no longerbiased by the bottom of the first locking device 20, and the slidingblock 55 itself is vertically slidable on the second locking device 50in the first place, the incurred ascent of the sliding block 55 causesthe locking block 54 to be pushed to the further right direction (seethe right half of FIG. 1) by the expansion of the horizontally deployedspring 53 and thus induces the lock pin 541 of the locking block 54 tobe fully extended. In other words, the bottom face 5412 of the lock pin541 is fully extended to lock itself in place to the lower hole 74 ofthe supporting tube 70. In such a manner, the locking block 54 isentirely locked into the lower hole 74 of the supporting tube 70, andthe second sliding tube 40 is also thus fixedly secured in place. Atthis time, the upper slopes 5422 of the triangular projections 542 areclosely engaged to the upper slope 554 of the sliding block 55 (see theleft half of FIG. 1).

[0028] Up to this point, if the user chooses to release the push button91 when the locking block's 24 guide pin 240 reaches the center hole 46of the second sliding tube 40, then followed by the secured allocationof the second sliding tube 40 on the supporting tube 70, the firstsliding tube 10 is also relocated when the locking block's 24 guide pinis engaged into the center hole 46 of the second sliding tube (see FIGS.3A and 3B); this accomplishes the retractable luggage handle lockingdevice's first protraction height option. In this manner, a uniquepurpose of carry-on handle for luggage piece of the present invention isthus attained. However, at this time, if the user chooses to keep onpressing the push button 91 and continues to pull up the first slidingtube 10 when the locking block 24 slips over the center hole 46 of thesecond sliding tube 40, then the first sliding tube 10 keeps on glidingupward until the locking block's 24 guide pin 240 reaches the top hole45. Here again, the user has two choices: if the user chooses to releasethe push button 91, then the first sliding tube 10 is once morerelocated to its second height position when the locking block's 24guide pin 240 is engaged into the top hole 45 (see FIGS. 4A and 4B);this accomplishes the retractable luggage handle locking device's secondprotraction height option. However, if the user chooses to keep onpressing the push button 91 and continues to pull up the first slidingtube 10 when the locking block 24 slips over the top hole 45 of thesecond sliding tube 40, then the first sliding tube 10 keeps on glidingupward until the longitudinal sliding block 55 of the second lockingdevice 50 is incurred to move upward. Sometime after the locking block24 (presently retracted due to the pressing of the push button 91) slipsover the top hole 45 on the second sliding tube 40 and before the momentwhen the top edge of the first locking device's 20 lower portion 214reaches the bottom end of the first sleeve member 30 and is stoppedthereat, the second connecting means' 56 top hook end 561 comes intoengagement with the upper platform of the first locking device 20. Sincethe escalating distance the first locking device 20 travels during thisvery short time period between the two engaging instants, when thelocking block's 24 guide pin 240 passes through the top hole 45 of thesecond sliding tube 40 and when the second connecting means' 56 top hookend 561 hits the upper platform of the first locking device 20 maypresent a great significance in the forthcoming discussion, it istherefore denoted here as the distance DELTA1. Since the secondconnecting means 56 is a slim rigid metal section with a bottom hook end562 clung to the arch-shaped hook receiver 552 on the upper portion 551of the sliding block 55, and also because there is a small distance leftbetween the contacting spot of the first locking device 20 and thesecond connecting means 56 and the clashing position of the firstlocking device 20 and the first sleeve member 30, the sliding block 55will move upward a small distance if the user keeps on lifting the firstsliding tube 10 until the lifting action is stopped by the mutualengagement of the first locking device 20 and the first sleeve member30. The lifting span of the sliding block 55 from its initial standstillposition to its later modestly lifted position exactly equals thedistance between the locus of the top edge of the first locking device's20 lower portion 214 when the first locking device 20 hits the secondconnecting means 56 at their tops and the bottom end position of thefirst sleeve member 30 at that same instant. Since this distance mayalso present great significance in our forthcoming discussion, it ishereby represented as the distance DELTA2.

[0029] The sliding block's 55 lifting reaction also causes the secondend 5412 of the lock pin 541 of the second locking device 50 to move tothe right to unlock itself from the lower hole 74 of the supporting tube70 (see FIGS. 5A and 5B). Since the user's first pressing of the pushbutton 91 on top of the luggage handle 90, the second sliding tube 40,even though originally not completely locked inside the supporting tube70 due to the initial semi-engagement of the lock pin 541 to the tube'slower hole 74, has always remained at the same lowermost position insidethe supporting tube 70. However, with the relief of the lock pin 541 inthe second locking device 50 from the lower hole 74 of the supportingtube 70, the second sliding tube 40 now also becomes maneuverable. Atthis time, however, if the user chooses to further pull up the luggagehandle, since the top edge of the first locking device's 20 lowerportion 214 is momentarily clashed with the bottom end of the firstsleeve member 30 and is stopped thereat (i.e., the first locking device20 and the first sliding tube 10 both have reached their higheststretching limit), the first sliding tube 10 and the second sliding tube40 together will move upward until the locking block 54 of the secondlocking device 50 comes into engagement with the top hole 73 of thesupporting tube 70 and locks itself therein (see FIGS. 6A and 6B).Within this stage of the locking device's movement (i.e., the resultingeffect of the user's sole manual action of continuously lifting theluggage's handle grip), before the lock pin 541 of the locking block 54enters the upper hole 73 of the supporting tube 70, the coupled actionof the first sliding tube 10 and the second sliding tube 40 containsseveral important features which later prove to be very useful for thehandle locking mechanism's follow-up movement. After the relief of thelock pin 541 of the second locking device 50 from the lower hole 74 ofthe supporting tube 70 and the subsequent physical collision between thetop edge of the first locking device's 20 lower portion 214 and thebottom end of the first sleeve member 30, the first sliding tube 10moves upward along with the second sliding tube 40 with no mutualrelative motion, and the frontal head of the locking pin 541 is forcedto lean against the inner wall of the supporting tube 70 and with itsother end severely biased by the compressed helical spring 53 when thesecond locking device 50 along with the second sliding tube 40 is beingpulled up. This suggests that the upward displacement of thelongitudinal sliding tube 55 w.r.t. the main body of the second lockingdevice 50, although initially enacted by the upward dragging forceevolved from the elevation of the first locking device 20 and theincurred tension of the rigid second connecting means 56, is not nowinduced by the dragging force passed from the top end of the secondconnecting means 56 but by the constant withdrawal of the locking block54 of the second locking device 50, during which time the rigid secondconnecting means 56 is not strained. Throughout this entire period, ifviewed from the side, the lower slope 5421 of the locking block's 54triangular shaped side protrusion leans against the lower slope 556 ofthe triangular shaped indentation provided at the lower portion 553 ofthe longitudinal sliding tube 55, which also means the locking block 54of the second locking device 50 is squeezed by the spring 53 andconfined inside the very limited cross sectional space of the supportingtube 70.

[0030] However, once the frontal head of the locking pin 541 of thelocking block 54 meets an opening (in this case, the opening is the tophole 73 of the supporting tube 70), the suppressed locking block 54,pushed by the compressed helical spring 53, will instantly move towardthe opening and exit the top hole 73 as far as the limiting frame behindthe lock pin 541 allows. During this process, the longitudinal slidingblock 55 will descend to its initial non-displaced position w.r.t. themain body of the second locking device 50, and if again viewed from theside, the locking block's 54 triangular shaped two protrusion sides 5422and 5421 now match precisely with the upper and lower sides 554 and 556,respectively, of the triangle shaped indentation provided at the lowerportion 553 of the longitudinal sliding tube 55. Up to this point,followed by the engagement of the lock pin 541 of the locking block 54to the upper hole 73 of the supporting tube 70, a small distance DELTA2(as defined earlier in the discussion), which originally was lifted forthe purpose of retracting the locking block 54 of the second lockingdevice 50 from the lower hole 74 on the supporting tube 70, now islowered again to accommodate a smooth protraction of the lock pin 541 ofthe locking block 54 from the upper hole 73 of the supporting tube 70.Nevertheless, remember that before the actual occurrence of the liftingaction of the small distance DELTA2, another small distance ascentDELTA1 was also lifted by the user; that elevation was for allowing thesecond connecting means' 56 top hook end 561 to contact the upperplatform of the first locking device 20 sometime after the lockingblock's 24 guide pin 240 slips over the top hole 45 of the secondsliding tube 40. Perceivably, the engagement of the locking block 54 ofthe second locking device 50 to the top hole 73 of the supporting tube70 does not guarantee another engagement of the first locking device's20 locking block 24 to the top hole 45 of the second sliding tube 40. Bystudying the relative positions among the first locking device 20, thefirst sleeve 30, and the engagement holes' 47, 46, and 45 respectiveloci on the second sliding tube 40, after the engagement of the lockingblock 54 of the second locking device 50 to the top hole 73 of thesupporting tube 70, there is still another small distance DELTA1 whichneeds to be descended by the first sliding tube 10 to facilitate asecond engagement of the first locking device's 20 locking block 24 tothe top hole 45 of the second sliding tube 40 (see FIGS. 6A and 6B).

[0031] The descent of the longitudinal sliding block 55 to its originalnon-displaced position on the second locking device 50 does not incur awhole bulk descent of the second locking device 50, yet the longitudinalsmall drop of the sliding block 55 does incur a sudden descent of thefirst locking device 20 through the actuation of a downward draggingforce induced by the second connecting means' 56 descent (because thesecond connecting means' 56 bottom hook end 562 is clung to thelongitudinal sliding block's 55 arch-shaped hook receiver 552 and itstop hook end 561 is clung to the top of the first locking device 20).Although the downward action of the first locking device 20 is onlyaffected by the second connecting means' 56 top hook end's 561 downwarddragging force when the second connecting means' 56 top hook end 561 isin contact with the top platform of the first locking device 20, yet themomentum evolved from the sudden descent of the first locking device 20continues on even after the separation of the first locking device 20from the second connecting means 56 and this momentum-related inertiafurther moves the first locking device 20 downward until the lockingblock's 24 guide pin 240 reaches the second sliding tube's 40 topengagement hole 45. At this time, since the push button is not pressed,the first connecting means 22 is therefore not activated, and therelease of the locking block 24 out of the second sliding tube's 40 topengagement hole 45 from the sudden expansion of the compressed helicalspring 23 is not in any way obstructed. As a result, the needed descentof another small distance DELTA1 of the first sliding tube 10, a smoothprotraction of the locking block's 24 guide pin 240 at the top hole 45of the second sliding tube 40, and the retractable luggage handlelocking device's third protraction height option are all accomplished(see FIGS. 7A and 7B). When the luggage handle is placed in a fullyextended position, owing to the locking device's multi-stroke designfeature, it can accommodate even the tallest user, allowing them to towthe luggage in considerable comfort.

[0032] The following is a description of the luggage handle's retractionoperation. The luggage handle's locking device momentarily is assignedto be at its initial highest protracted position (see FIGS. 7A and 7B),and the luggage's push button stays as non-depressed. When the userpresses the push button, however, the first connecting means 22 isstrained and pulled up. Since the first connecting means 22 is in theform of a curvilinearly deformable steel cable, the first connectingmeans 22 ascending action causes the guide pin 240 of the horizontallyallocated locking block 24 to retract from the top hole 45 of the secondsliding tube 40 and thus releases the first sliding tube 10 from itsprotractedly locked position. A ground is given to the user to furtherpush down the first sliding tube 10 and retract it into the secondsliding tube 40. This further lowering operation of the first slidingtube 10 causes the guide pin 240 of the horizontally-allocated lockingblock 24 to slip through the center hole 46 of the second sliding tube40 while the lock pin 541 on the locking block 54 is still protractedlysecured to the upper engagement hole 73 of the supporting tube 70. Atthis time, if the user chooses to release the push button, the guide pin240 is immediately launched by the compressed spring 23 and comes out ofthe center hole 46 of the second sliding tube, which accomplishes theretractable luggage handle locking device's fourth protraction heightoption. Since the reaction is a lowering operation for the first slidingtube 10, the luggage handle's fourth height option is uprightly shorterthan its third height option but is taller than the second heightoption. However, if the user chooses to continue pressing the handle'sbutton and meanwhile pushes further down the first sliding tube 10, theguide pin 240 of the horizontally allocated locking block 24 slips overthe center hole 46 of the second sliding tube 40 and continues todescend while the lock pin 541 on the locking block 54 is stillprotruded at the upper hole 73 of the supporting tube 70. At this time,the bottom of the first locking device 20 comes into contact with thetop of the sliding block 55. The lower portion 214 of the first lockingdevice 20 then pushes down the top of the sliding block 55 to cause theupper slopes 554 of the sliding block 55 to press against the upperslopes 5422 of the triangular projections 542, thus pulling in the lockpin 541 of the second locking device 50 from the upper hole 73 of thesupporting tube 70. With the release of the engagement pin 541 from theupper hole 73 of the supporting tube 70, the second sliding tube 40 isfree to be retracted into the supporting tube 70, and if the userchooses to push down the first sliding tube 10 and the second slidingtube 40 all the way down to their respective lower hole positions, thelocking device eventually returns to its initial fully retractedlocation (as seen in FIGS. 2A and 2B). Thus, the cycle of theprotraction-retraction operation is completed.

[0033] In the preferred embodiment the first locking device 20 is aprimary component and the second locking device 50 is a supplementarycomponent in the luggage handle's locking mechanism. Thus in otherembodiments, the number of the second locking devices 50 and the numberof the second sliding tubes 40 may be increased. As a result, it ispossible to produce luggage handle systems having a plurality ofconstituent tubes along with their adjoining locking devices, resultingin a great variety of luggage handle protraction heights.

[0034] Note that the provision of the cable 56 and the center hole 46 ofthe second sliding tube 40 may be omitted if the design requirement doesnot include the pre-assigned first protraction height of the luggagehandle, which is a small lifting length that allows the luggage handleto be extended a small distance on top of the luggage body toaccommodate the smooth undertaking of a minor loading situation.

[0035] Also note that the length of the elongated upper portion 210 ofthe first locking device 20 is designed to be longer than the length ofthe first sleeve member 30. This is especially designed to strengthenthe connection between the first sliding tube 10 and the second slidingtube 40, because often this spot turns out to be the Achilles' heel forluggage handle design.

[0036] It is important to note that the most crucial innovation in thepresent invention is with the second locking device 50. If, for example,the second locking device 50 is not provided, then, in order to maintainthe multi-stroke handle system's normal function, another locking devicevery similar to the present first locking device 20 may have to beemployed instead. With the addition of another locking device 20 toreplace the present second locking device 50, not only must the handlesystem include two independent control chains fitted into one tinyspace, but also the user may have to press the two separate controlbuttons twice to achieve the luggage handle's protraction-retractionoperation. By using such a design, the luggage handle's lockingmechanism becomes clumsy, complicated, and easy to malfunction. In thepreferred embodiment, the second locking device 50 is simplified tocomprise only the two housings 51 and 52, one horizontally allocatedspring 53, one horizontally deployed locking block 54, a longitudinalsliding block 55, and a second connecting means 56. Amongst them, theuprightly located sliding block 55, the lateral locking block 54, andthe second connecting means 56 (perhaps in the form of a slim rigidmetal section) are actually the three threshold elements within thesecond locking device 50. As stated above, the upper and the lowerslopes 5421 and 5422 of the locking block 54 engage, respectively,against the upper slope 554 and the lower slope 556 of the sliding block55. Also, with the top and the bottom hook ends 561 and 562 of thesecond connecting means 56 attached, respectively, to the guide groove212 on the first housing 21 and the protruded groove 552 on the upperportion 551 of the sliding block 55, the locking functions as describedabove are accomplished.

[0037] While the invention herein disclosed has been described by meansof specific embodiments, numerous modifications and variations could bemade thereto by those skilled in the art without departing from thescope of the invention set forth in the claims.

What is claimed is:
 1. A handle assembly of wheeled luggage provided ona back portion of the luggage, the luggage having: a handle with ahandle grip (90) having opposing ends and a push button (91) locatedbetween the ends and operable at a first position and a second position;a pair of first sliding tubes (10) connected to the respective ends ofthe handle grip; a pair of second sliding tubes (40), slidably engagedwith the first sliding tubes (10) for allowing the respective firstsliding tubes to slide therein; and a pair of supporting tubes (70),slidably engaged with the second tubes (40) for allowing the secondtubes to slide therein when the handle is pulled upward to a usedposition and pushed downward to a stored position, said assemblycomprising: a pair of first locking devices (20) operatively connectedto the push button (91); and a pair of second locking devices (50),engaged with the respective supporting tubes (70), for securing thesecond tubes (40) to the respective supporting tubes (70) in a lockedposition when the handle is operated in the stored position, wherein thesecond locking devices (50) are operatively connected to the respectivefirst locking devices (20) for allowing the first locking devices (20)to release the respective second locking devices (50) from the lockedposition when the push button is operated in the first position.
 2. Thehandle assembly of claim 1, wherein each of the supporting tubes (70)has a hole (74) and each of the second locking devices (50) has alocking pin (541) for engaging with the hole (74) in the respectivesupporting tube when the second locking devices are operated in thelocked position, and disengaged from the hole (74) when the secondlocking devices are released from the locked position.
 3. The handleassembly of claim 2, wherein each the second locking devices (50)further comprises a sliding block (55) located adjacent to andoperatively engaged with the respective locking pin (541), and whereinthe sliding block (55) is connected to the respective first sliding tube(10) by a connecting means (56) for pulling the sliding block away fromthe respective locking pin (541), thereby causing the locking pin (541)to disengaged from the hole (74) when the handle is pulled upward to theused position.
 4. The handle assembly of claim 3, wherein each of thefirst locking devices has a guiding pin (240) which can be engaged withan aperture (47) on the respective second sliding tube (40) in asecuring position to prevent the handle from being pulled upward whenthe push button is operated in the second position, and wherein theguiding pin (24) is disengaged from the aperture (47) when the pushbutton is operated in the first position.
 5. The handle assembly ofclaim 4, wherein each of the first locking devices is operativelyconnected to the push button by a further connecting means (22) fordisengaging the guiding pins (24) from the respective aperture (47) whenthe push button is operated in the first position.
 6. The handleassembly of claim 5, wherein each of the second sliding tubes (40)further having a further aperture (45) for engaging with the respectiveguiding pin (240) to secure the first sliding tube (10) to therespective second sliding tube (40) when the handle in operated in theused position.
 7. The handle assembly of claim 4, wherein each of thesupporting tubes (70) further having a further hole (73) for engagingwith the respective locking pin (541) to secure the second sliding tube(40) to the respective supporting tube (70) when the handle is operatedin the used position.
 8. The handle assembly of claim 3, wherein each ofthe first locking devices has a guiding pin (240) which can be engagedwith an aperture (46) on the respective second sliding tube (40) in asecuring position to have the handle used as a carry-on handle andprevent the handle from being further pulled upward when the push buttonis operated in the second position, and wherein the guiding pin (24) isdisengaged from the aperture (46) when the carry-on handle is not usedand the push button is operated in the first position.
 9. The handleassembly of claim 2, wherein each of the second locking devices (50)further comprises a sliding block (55) located adjacent to andoperatively engaged with the respective locking block (54), and whereinthe sliding block (55) has a rectangular recess and two V-shapedrecesses located on two opposing sides of the rectangular recess, eachV-shaped recess having an upper slope and a lower slope, and wherein thelocking block (54) has two triangular projections, each triangularprojection having a lower slope and an upper slope, which are providedon the two opposing outer surfaces of the locking block (54), forlaterally coupling with the upper slope and the lower slope of theV-shaped recesses of the lower portion of the longitudinal slidingblock, when the push button is operated in the first and secondpositions.